Q. For fourth order reaction, what is the unit of K?
A) $\left( \frac{mol}{L} \right)^{- 3}s^{- 1}$
B) $\left( \frac{mol}{L} \right)^{+ 3}s^{- 1}$
C) $\left( \frac{mol}{L} \right)^{- 3}s$
D) $\left( \frac{mol}{L} \right)^{- 3}$
Explanation
(a)
Unit of $k = conc^{1 - n}t^{- 1}$
$\left( \frac{mol}{L} \right)^{1 - 4}t^{- 1}$
$\left( \frac{mol}{L} \right)^{- 3}t^{- 1}$
Therefore, the unit of k is
$\left( \frac{mol}{L} \right)^{- 3}t^{- 1}$ for fourth order reaction.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.